Methods for treatment of headaches by administration of oxytocin

ABSTRACT

The present invention relates to methods for the treatment of headache and headache disorders. The methods comprise administration of an oxytocin peptide for the treatment of primary and secondary headaches or trigeminal neuralgia.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 12/210,866, filed on Sep. 15, 2008 now U.S. Pat.No. 8,198,240, which is a continuation application of U.S. applicationSer. No. 11/511,997, filed Aug. 28, 2006 now abandoned , which claimsthe benefit of U.S. Provisional Patent Application Ser. No. 60/711,950,filed Aug. 26, 2005 and U.S. Provisional Patent Application Ser. No.60/794,004, filed Apr. 21, 2006, the entire contents of which are herebyincorporated by reference in their entirety.

TECHNICAL FIELD

The present invention relates generally to methods and compositions forthe treatment of headache and headache or head pain disorders. Morespecifically, the present invention relates to methods for the treatmentor prevention of primary or secondary headaches by administration ofoxytocin. In particular, the present invention relates to methods forthe treatment or prevention of migraine, cluster, tension headaches ortrigeminal neuralgia by administration of oxytocin or pharmaceuticalcompositions comprising oxytocin to individuals in need of treatment.

BACKGROUND OF THE INVENTION

Although the epidemiology of headache disorders is only partlydocumented, taken together, headache disorders are extraordinarilycommon. It has been estimated that worldwide approximately 240 millionpeople have migraine attacks each year. The National Headache Foundationstates that more than 29.5 million Americans suffer from migraineheadaches, with women being affected three times more often than men. Inaddition, in developed countries, tension type or “stress” headaches areestimated to affect two-thirds of all adult males and over 80% of adultfemales. Less well known is the prevalence of chronic daily headachesalthough the World Health Organization (WHO) estimates that one adult in20 has a headache every or nearly every day. Trigeminal neuralgia is nota common disorder but the pain associated with trigeminal neuralgiaattacks has been described as among the most severe known to mankind.

Not only are headaches painful, but headache disorders can be disablingto afflicted individuals. Worldwide, according to the WHO, whenanalyzing all causes for “years lived with disability” migraineheadaches were rated 19th on the list. Headache disorders may imposesubstantial hardships and burdens on the afflicted individuals includingpersonal suffering, impaired quality of life and high financial cost.Repeated headache attacks, and often the constant fear of the next one,can damage an individual's family life, social life and theirproductivity at their place of employment. For example, it is estimatedthat social activity and work capacity are reduced in almost allmigraine sufferers and in 60% of tension headache sufferers. Finally,the long-term effort of coping with a chronic headache disorder may alsopredispose an individual to other illnesses. For example, depression isthree times more common in people with migraine or severe headaches thanin healthy individuals.

A wide range of headache types have been classified by the InternationalHeadache Society and among them are primary types including vascular,trigemino-autonomic and tension headaches and secondary types includingheadaches resulting from infection, trauma and non-vascular,intracranial disorders.

Vascular headaches refer to a group of headache conditions in whichevents at the interface between meningeal blood vessels and afferentnerve fibers are critical major components in the production of pain.Afferent nociceptive nerve fibers innervating meningeal blood vesselsbecome activated in response to inflammatory and related events at theperi-vascular sheet causing a throbbing or pulsating type of pain. Themost common type of vascular headache is migraine. Currentpathophysiological evidence suggests that the trigemino-vascular systemplays a pivotal role in the genesis of migraine headache. Migraineheadache characteristics include unilateral (60%) or bilateral headpain, pain with a pulsating or throbbing quality, moderate to severepain, pain associated with nausea or vomiting, sensitivity to light andsound, attacks that last four to 72 hours (sometimes longer) and visualdisturbances or aura. Physical exertion often makes a migraine headacheworse and women are more likely than men to have migraine headaches.Approximately one to two-fifths of migraine sufferers experience anaura, a sensory phenomena including visual disturbances that precede theonset of migraine headache. It is now believed that the aura is due totransient changes in the activity of specific nerve cells.

Another type of primary vascular headache is “cluster” headache, whichis diagnosed by a well characterized clinical presentation. Although thesyndrome is well defined from a clinical point of view, the causes arenot well understood. The pathophysiology is believed to be associatedwith the trigemino-autonomic system. The periods during which clusterheadache is experienced can last several weeks or months and thendisappear completely for months or years leaving pain-free intervalsbetween headache series. Cluster headache is characterized by frequentattacks of short lasting (15-180 minutes), severe, uniform, unilateralhead pain associated with autonomic symptoms (e.g. lacrimation and nasalcongestion). Pain can occur on the opposite side when a new seriesstarts, pain may be localized behind the eye or in the eye region andmay radiate to the forehead, temple, nose, cheek or upper gum on theaffected side. Pain is generally extremely intense and severe and oftendescribed as a burning, boring, stabbing or piercing sensation. Theheadaches occur regularly, generally at the same time each day. Manyindividuals get one to four headaches per a day during a cluster period.Cluster headache is less common than migraine or tension headache andits cause is unknown. In contrast to migraine headaches, clusterheadaches occur more in men than women and individuals suffering fromthese attacks may be very restless.

Tension headache, often referred to as “stress” headache, is anon-specific type of primary headache, which is of non-vascular originand rarely is related to an organic disease. The pathophysiology oftension headaches is thought to involve the myo-facial system. Forexample, tension headache may be caused by the tightening of facial andneck muscles, clenching or grinding of teeth and/or poor posture.Tension headaches can be episodic and chronic in course, and typicallyare of mild to moderate intensity. Verbal descriptor used tocharacterize tension headache include pressing, dull aching and/ornon-pulsating. Tension head pain is typically bilateral, and is notaggravated by physical activity.

Trigeminal neuralgia, also called “tic duloreaux” is a condition thataffects the trigeminal nerves and results in severe facial and headpain. Trigeminal neuralgia most commonly is diagnosed in patients overage 50, is slightly more common in women and has an incidence ofapproximately 4-5 per 100,000 persons. Trigeminal neuralgia ischaracterized by sudden severe, sharp facial pain, which usually startswithout warning. The quick bursts of pain are described as “lighteningbolt-like”, “machine gun-like” or “electric shock-like”. The pain isgenerally on one side of the face and is spasmodic, coming in shortbursts lasting a few seconds which may repeat many times over the courseof a day. Trigeminal neuralgia can involve one or more branches of thetrigeminal nerve and the causes are not well characterized.

Current Treatments

There are numerous treatment strategies for migraine and associatedsymptoms (e.g. nausea). However, to date, there is no single treatmentstrategy (including prevention or prophylaxis) that successfullyalleviates migraine in a majority of patients. Additionally, treatmentthat has proven effective in one particular migraine sufferer may onlybe partially or intermittently effective. The current standard of carefor migraine focuses on three major areas: 1) acute or abortivetreatment; 2) treatment to relieve specific symptoms; and 3) preventivetreatment.

Abortive treatment is always indicated because of the disabling natureof migraine attacks. Sumitriptan and related 5-hydroxytryptamine(5-HT-1, serotonin) receptor agonists (triptans) are often consideredthe therapy of choice for migraine headache. To show optimaleffectiveness, these agents generally have to be given early in theonset of pain. Serotonin receptor agonists are effective in up to 70% ofpatients and generally have few side effects when used sporadically. Thenumber of patients benefiting from treatment with triptans may decreaseto less than 50% during long-term therapy. Despite being effective,serotonin receptor agonists often only partially attenuate migraineheadache. Rebound pain frequently occurs during the time period duringwhich the drug levels are falling. Furthermore, side effects may ariseincluding dizziness, heaviness or pressure on the chest and arms,shortness of breath, and sometimes chest pain which limit their clinicalutility. Triptans are contra-indicated for patients with coronary arterydisease. Other members of this class of drugs include, but are notlimited to, sumatriptan, zolmitriptan, naratriptan, rizatriptan andelitriptan. Other classes of drugs that are used to treat migraineinclude the nonsteroidal anti-inflammatory drugs (NSAIDs), ergotaminesand on occasion, neuroleptic drugs such as compazine. NSAIDS are aseffective as triptans in alleviating migraine headache when given at theonset of mild migraine headache. Ergotamines, although commonlyprescribed, are less effective than triptans and NSAIDS. Opioids such ascodeine and butorphanol are not a first choice for the treatment ofmigraine because of their limited effectiveness, associated side effectsincluding sedation and respiratory depression and the potential fordependence and abuse.

Preventive treatment strategies are considered whenever migraine attackshave occurred several times in a month or are very severe and do notrespond well to abortive medication. The following classes of drugs areused for preventing migraine: beta-blockers (e.g. propranolol,metoprolol, atenolol), calcium channel blockers, NSAIDs,antidepressants, anti-convulsant drugs (e.g. divalproex sodium,topiramate) and methysergide (no longer available in the United States).Another avenue for preventive treatment is educating the migrainepatient to recognize and avoid migraine triggers which may help toreduce the frequency of attacks. Common migraine triggers include, butare not limited to, weather changes, bright lights, strong odors, stressand foods.

In a significant number of patients abortive and preventive treatmentsfor migraine headache are often either ineffective, only partiallyeffective or associated with significant side effects includinghypotension, tiredness, increased weight, breathlessness, dizziness,heaviness or pressure on the chest and arms, shortness of breath, chestpain, nausea, muscle cramps, or peripheral vasoconstriction.

Treatment strategies for cluster headache are classified as abortive orpreventive. Abortive treatments are directed at stopping or reducing theseverity of an attack, while preventive treatments are used to reducethe frequency and intensity of individual headache bouts. Abortivetreatment strategies of cluster headache are quite successful when drugscan be injected. Drug classes used for injection include the5HT1-agonists (e.g. sumatriptan) and the ergotamines. Alternatively,inhalation of 100% oxygen or an occipital nerve block have proveneffective. However, all these treatment strategies require a visit to adoctor's office or to an emergency room.

Because of the short-lived nature of cluster headaches, preventivetherapy is the cornerstone for individuals who have frequent attackswhich severely affect their quality of life. Preventive therapy isinitiated at the start of a cluster headache cycle and continues untilthe person is free of headaches for at least 2 weeks. The dosage of thepreventive drug is then slowly tapered off which helps prevent relapsingheadaches. Drug classes used preventively include beta-blockers,tricyclic antidepressants, anti-convulsants (e.g., divalproex sodium,topiramate), calcium channel blockers (e.g., verapamil), cyproheptadine,and NSAIDs (e.g. naproxen). Unlike drugs that ablate cluster headache(abortive drugs), most of the drugs used to prevent cluster headachehave been developed for other clinical conditions and unfortunately,their effectiveness in prevention is limited.

Treatment for tension headache usually consists of nonprescriptionpainkillers such as aspirin, acetaminophen, NSAIDs or combinations ofthese agents with caffeine or sedating medications. When severe musclecontraction is present and/or the tension headache becomes chronic, morepowerful prescription drugs may be needed to achieve relief. Tricyclicanti-depressants including amitriptyline HCl, doxepin HCl andnortriptyline HCl are commonly used. However these drugs havesignificant side effects including sedation, weight gain, dry mouth andconstipation.

The first line treatment of trigeminal neuralgia is pharmacological innature and is based on the use of antiepileptic agents includinggabapentin, baclofen, clonazepam, lamotrigine, oxcarbazepine, toprimateand carbamazepine. About 50% of patients initially respond to treatmentwith a single agent and about 70% respond to treatment with two agents.However, a significant portion of patients (>50%) eventually becomesrefractory to drug treatment and adding of a third agent or an analgesicdrug (opioid or a non-steroidal anti-inflammatory agent) does notimprove therapeutic success. Therapy with antiepileptic agents is alsoassociated with side effects, most prominently dizziness, drowsiness,and ataxia. Many antiepileptic agents have the potential to cause rarebut serious reactions.

Considering surgical interventions is the next appropriate step inpatients who are refractory to pharmacological interventions. Surgicaltechniques include radio-frequency ablation of the trigeminal ganglion,micro-vascular decompression of the trigeminal root and gamma-kniferadiation to the trigeminal root. The success rate of surgicaltechniques is initially quite high (80-90%) while the longer termsuccess is closer to 50%. Specific side effects of these surgicalinterventions are sensory loss (numbness) and/or dysesthesia (e.g.analgesia dolorosa) in the distribution of the trigeminal nerve.Micro-vascular decompression in particular can be complicated by theoccurrence of meningitis, cerebrospinal fluid leaks, or cranial nervedeficits. This procedure requires a craniotomy and the publishedmortality rate for this procedure is significant at 0.2-1.2%.

It is clear that migraine, cluster and tension headaches as well astrigeminal neuralgia can be debilitating to individuals andsignificantly impair their quality of life. To date, there does notappear to be a class of drugs or a treatment regimen that is effectivefor a majority of patients suffering from primary or secondary headachesor suffering from trigeminal neuralgia. Therefore, there is still agreat need for novel and more effective therapies preventing oralleviating head pain of any origin.

BRIEF SUMMARY OF THE INVENTION

Provided herein are methods for the treatment of headache or trigeminalneuralgia comprising administering to an individual an effective amountof an oxytocin peptide. Some aspects of the invention include methodswherein the oxytocin peptide is administered in combination with atleast one additional analgesic agent. Some aspects of the inventioninclude methods wherein the administration results predominantly inanalgesia to the facial or head region, as compared to analgesic effectsin other parts of the body, and in alleviation of the headache pain.Some aspects of the invention include methods wherein the headache painis a result of a primary headache or a secondary headache. In someexamples the primary headache is a vascular headache or a tension-typeheadache. In some examples the vascular headache is a migraine or acluster type headache. In some examples the secondary headache resultsfrom an infection, ingestion of toxin, or over-consumption of alcohol.Other aspects of the invention include methods wherein the head pain isa result of trigeminal neuralgia.

Provided herein are methods for the treatment of headache or trigeminalneuralgia pain in an individual, comprising administering to theindividual an effective amount of an oxytocin peptide. In some aspectsof the invention, the oxytocin peptide is administered via mucosaladministration. In some examples the oxytocin peptide is administeredintranasally. In other examples the oxytocin peptide is administered viabuccal or sublingual administration. In other examples the oxytocinpeptide is administered to conjunctiva or other mucosal tissues aroundthe eye. In some aspects of the invention, the oxytocin peptide isadministered via transdermal administration. In some examples theoxytocin peptide is administered to the skin or dermal surface. In otherexamples the oxytocin peptide is administered to the skin by intradermalor subcutaneous injection. In some examples the oxytocin peptide istargeted to the trigeminal nerve system and results predominantly inanalgesia to the facial or head region.

Some aspects of the invention include methods for prevention of headachepain or trigeminal neuralgia comprising administering to an individualin need thereof an effective dose of an oxytocin peptide. In someaspects of the present invention, the methods comprise prophylactictreatment for migraine-associated pain comprising administering anoxytocin peptide to an individual experiencing a migraine-associatedaura prior to onset of a migraine headache. In some aspects of thepresent invention, the methods comprise prophylactic treatment forcluster headache pain comprising administering an oxytocin peptide to anindividual after a cluster series has started but prior to successiveheadaches in the cluster series. In some aspects of the presentinvention, the methods comprise prophylactic treatment for trigeminalneuralgia pain comprising administering an oxytocin peptide to anindividual after a trigeminal neuralgia attack but prior to successiveattacks.

Some aspects of the invention include methods wherein an oxytocinpeptide is administered as a pharmaceutical composition. Accordingly,provided herein are methods for treatment and/or prevention of headachepain or trigeminal neuralgia in an individual, comprising: administeringto the individual an effective amount of a pharmaceutical compositioncomprising an oxytocin peptide wherein the oxytocin peptide isadministered via intravenous injection, subcutaneous injection, mucosalor transdermal administration. Some aspects of the invention includemethods wherein the pharmaceutical composition further comprises atleast one additional analgesic agent. Some aspects of the inventioninclude methods wherein the pharmaceutical composition is administeredin a formulation selected from a group comprising a powder, a liquid, agel, a film, an ointment, a suspension, a cream or a bioadhesive. Someaspects of the invention include methods wherein the pharmaceuticalcomposition further comprises a protease inhibitor, an absorptionenhancer, a vasoconstrictor or combinations thereof. In some examples,the protease inhibitor is selected from a group comprising antipain,arphamenine A and B, benzamidine HCl, AEBSF, CA-074, calpain inhibitor Iand II, calpeptin, pepstatin A, actinosin, amastatin, bestatin,chloroacetyl-HOLeu-Ala-Gly-NH₂, DAFT, diprotin A and B, ebelactone A andB, foroxymithine, leupeptin, pepstatin A, phosphoramidon, aprotinin,BBI, soybean trypsin inhibitor, phenylmethylsulfonyl fluoride, E-64,chymostatin, 1,10-phenanthroline, EDTA and EGTA. In some examples theabsorption enhancer is selected from a group comprising surfactants,bile salts and analogues thereof (e.g. sodium taurodihydrofusidate),bioadhesive agents, phospholipid additives, mixed micelles, liposomes,or carriers, alcohols, enamines, cationic polymers, NO donor compounds,long-chain amphipathic molecules, small hydrophobic penetrationenhancers; sodium or a salicylic acid derivatives, glycerol esters ofacetoacetic acid, cyclodextrin or beta-cyclodextrin derivatives,medium-chain fatty acids, chelating agents, amino acids or saltsthereof, N-acetylamino acids or salts thereof, mucolytic agents, enzymesspecifically targeted to a selected membrane component, inhibitors offatty acid synthesis and inhibitors of cholesterol synthesis.

Provided herein are methods for treatment and/or prevention of headachepain or trigeminal neuralgia in an individual comprising administeringto the individual i) an effective amount of a pharmaceutical compositioncomprising an oxytocin peptide and ii) a vasoconstrictor. Generally,administration of the vasoconstrictor reduces systemic distribution ofthe oxytocin peptide. In some examples the vasoconstrictor is selectedfrom the group comprising phenylephrine hydrochloride, tetrahydrozolinehydrochloride, naphazoline nitrate, oxymetazoline hydrochloride,tramazoline hydrochloride, ergotamine, dihydroergotamine, endothelin-1,endothelin-2, epinephrine, norepinephrine and angiotensin. In someexamples the vasoconstrictor is administered prior to the administrationof the pharmaceutical composition. In other examples the vasoconstrictoris co-administered with the pharmaceutical composition. In some examplesadministration of the vasoconstrictor results in a decreased effectivedosage requirement of the oxytocin peptide. In other examples thepharmaceutical composition further comprises at least one additionalanalgesic agent.

Provided herein are methods for treatment and/or prevention of headachepain or trigeminal neuralgia in an individual comprising administeringto the individual an effective amount of a pharmaceutical compositioncomprising an oxytocin peptide. In some examples, the oxytocin peptideis administered via buccal or sublingual administration. In otherexamples, the pharmaceutical composition is administered by intranasaladministration. In some examples, the pharmaceutical composition isadministered by intranasal administration to the nasal cavity. In oneexample the intranasal administration is directed to the inferiortwo-thirds of the nasal cavity. In another example the administration isdirected to the inferior region of the nasal cavity, thus directing itaway from the nasal mucosal region innervated by the olfactory nerve. Insome examples the pharmaceutical composition is administered bytransdermal, intradermal or subcutaneous administration to the skin ordermal surface.

Provided herein are methods for treatment and/or prevention of headachepain or trigeminal neuralgia in an individual comprising administeringto the individual an effective amount of an oxytocin peptide or apharmaceutical composition comprising an oxytocin peptide in combinationwith an additional active agent. In some examples the pharmaceuticalcomposition further comprises at least one additional active agent. Inother examples the pharmaceutical composition further comprises at leasttwo additional active agents. In some examples the additional activeagent is selected from the group consisting of non-peptide opioids,opioid and opioid-like peptides and their analogs, NMDA-receptorantagonists, sodium channel blockers, calcium channel blockers,adrenergic antagonists, gabaergic agonists, glycine agonists,cholinergic agonists, adrenergic agonists, such as epinephrine,anticonvulsants, Rho kinase inhibitors, PKC inhibitors, p38-MAP kinaseinhibitors, ATP receptor blockers, endothelin receptor blockers,pro-inflammatory cytokine blockers, pro-inflammatory chemokine blockers,pro-inflammatory interleukin blockers and tumor necrosis factorblockers, anti-inflammatory cytokines, tricyclic antidepressants,serotonergic antagonists, serotonergic agonists, NSAIDs and COXIBs,acetaminophen; analgesic peptides, toxins, TRP channel agonists andantagonists, cannabanoids, antagonists of pro-nociceptive peptideneurotransmitter receptors CGRP1 and CGRP2, antagonists ofpro-nociceptive peptide neurotransmitter receptor NK1, antagonists ofpro-nociceptive peptide neurotransmitter receptor NK2, antagonists ofpro-nociceptive peptide neurotransmitter receptor Y1-5, antagonists ofpro-nociceptive peptide neurotransmitter receptors VPAC2, VPAC1 andPAC1, antagonists of pro-nociceptive peptide neurotransmitter receptorreceptors Gal1-3 and GalR1-3, agonists or antagonists of vasopressin,corticotropin releasing hormone (CRH), growth hormone releasing hormone(GHRH), luteinizing hormone releasing hormone (LHRH), somatostatingrowth hormone release inhibiting hormone, thyrotropin releasing hormone(TRH), glial-derived neurotrophic factor (GDNF), brain-derivedneurotrophic factor (BDNF), nerve growth factor (NGF), neurotrophin-3(NT-3), pancreatic polypeptide, peptide tyrosine-tyrosine, glucogen-likepeptide-1 (GLP-1), peptide histidine isoleucine (PHI), pituitaryadenylate cyclase activating peptide (PACAP), brain natriuretic peptide,cholecystokinin (CCK), islet amyloid polypeptide (IAPP) or amylin,melanin concentrating hormone (MCH), melanocortins (ACTH, α-MSH andothers), neuropeptide FF (F8Fa), neurotensin, parathyroid hormonerelated protein, calcitonin, Agouti gene-related protein (AGRP), cocaineand amphetamine regulated transcript (CART)/peptide, 5-HT-moduline,hypocretins/orexins, nociceptin/orphanin FQ, ocistatin, prolactinreleasing peptide, secretoneurin, urocortin and derivatives andanalogues thereof. In some examples the additional active agent isdiclofenac.

Provided herein are methods for treatment and/or prevention of headachepain or trigeminal neuralgia in an individual comprising administeringto the individual an effective amount of an oxytocin peptide or apharmaceutical composition comprising an oxytocin peptide. In someexamples, administration of an oxytocin peptide or a compositioncomprising an oxytocin peptide results in reduction of a pain rating onthe VAS of 30% or more. In other examples, administration of an oxytocinpeptide or a composition comprising an oxytocin peptide results inreduction of a pain rating on the VAS of 50% or more.

Provided are kits for carrying out any of the methods described herein.Kits are provided for use in treatment and/or prevention of headachepain and headache disorders. Kits of the invention comprise an oxytocinpeptide in suitable packaging. Some kits may further comprise at leastone additional analgesic agent. Some kits may further comprise avasoconstrictor, at least one protease inhibitor, and/or at least oneabsorption enhancer. Some kits may further comprise a delivery device,including but not limited to, a device for intranasal administration.The kits may further comprise instructions providing information to theuser and/or health care provider for carrying out any of the methodsdescribed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts data demonstrating withdrawal latencies after noxiousthermal stimulation to the ears or hindpaws in a rat model afterintranasal administration of oxytocin. Rats were intranasallyadministered 10 μg oxytocin and withdrawal latencies were tested. Eachdata point represents the average, across 8 animals, of latencies inresponse to stimulation at a particular time after the beginning of thetest. The circles represent the withdrawal latencies after thermalstimulation to the ear in control rats treated with saline. The squaresrepresent the withdrawal latencies after thermal stimulation to the earin rats treated with 10 μg oxytocin. The triangles represent thewithdrawal latencies after thermal stimulation to the hindpaw in thetreated rats.

FIG. 2 depicts the effect of intranasal administration of oxytocin ontrigeminal nerve impulses in response to noxious laser pulses to theface in a rat model. Data demonstrating average nerve impulses afternoxious laser pulses to the face pre- and post-treatment are shown.

FIGS. 3A-3D depict the effect of intranasal administration of oxytocinon electrical stimulus-induced responses of trigeminal nucleus caudaliswide dynamic range neurons. FIG. 3A shows responses (action potentialsper 30 stimuli) to repeated stimulation of a rat's face before and afteroxytocin administration. FIG. 3B shows the approximate site (black spot)of administration on the rat's face of the electrical administration.FIG. 3C shows raw data recorded during electrical stimulation beforeoxytocin administration. FIG. 3D. shows raw data recorded duringelectrical stimulation 30 minutes after intranasal oxytocinadministration.

DETAILED DESCRIPTION OF THE INVENTION Definitions

As used herein, unless otherwise specified, the term “treatment” or“treating pain” refers to administration to an individual of an agent ofinterest wherein the agent alleviates or prevents a pathology for whichthe individual is being treated. “Treatment for headache pain”,“treatment of headache” or “treatment of head pain” refers to thealleviation or prevention of pain associated with headache disorders andtrigeminal neuralgia.

As used herein, unless otherwise specified, the term “prevention”,“prophylaxis” or “preventing pain” refers to administration to anindividual of an agent of interest wherein the agent alleviates orprevents a pathology for which the individual is being treated.“Prevention of headache pain”, “prevention of headache” or “preventionof head pain” refers to the alleviation or prevention of pain associatedwith headache disorders and trigeminal neuralgia.

As used herein, “central nervous system” or “CNS” refers to that part ofthe nervous system that is embedded in cerebrospinal fluid (CSF)including the brain, the spinal cord and proximal aspects of peripheralnerves entering the space embedded in CSF. The CNS is one of the twomajor divisions of the nervous system. The other is the peripheralnervous system which is outside of the brain and spinal cord andincludes the peripheral portions of the cranial nerves—of which thetrigeminal nerve is a member.

Although analgesia in the strictest sense is an absence of pain, as usedherein, “analgesia” refers to reduction in the intensity of the painperceived by an individual without causing general numbness.

As used herein, “analgesia agent”, “analgesic agent” or “analgesic”refers to any biomolecule, drug or active agent that alleviates orprevents pain.

As used herein, “oxytocin” or “oxytocin peptide” refers to a substancehaving biological activity associated with natural oxytocin. Oxytocin oroxytocin peptide can be a naturally occurring endogenous peptide,fragments, analogues or derivatives thereof. Oxytocin or oxytocinpeptide can also be a non-endogenous peptide, fragments, analogues orderivatives thereof.

As used herein “analogues and derivatives” refers to any peptideanalogous to naturally occurring oxytocin wherein one or more aminoacids within the peptide have been substituted, deleted, or inserted.The term also refers to any peptide wherein one or more amino acids havebeen modified, for example by chemical modification. In general, theterm covers all peptides which exhibit oxytocin activity but which may,if desired, have a different potency or pharmacological profile.

As used herein, “migraine” includes migraine headache, migraine withoutaura, migraine with aura, and migraine with aura but without headache.

As used herein, “cluster headache” includes cluster headache,cluster-type headache, histamine headache, histamine cephalalgia,Raedar's syndrome, and sphenopalatine neuralgia.

As used herein, “tension headache” includes tension headache,tension-type headache, muscle contraction headache and stress headache.

As used herein, “headache disorder” includes migraine, tension headache,cluster headache, trigeminal neuralgia, secondary headaches, andmiscellaneous-type headache.

As used herein, “pain” includes acute pain, chronic pain and episodicpain.

As used herein “systemic side effects” include, but are not limited to,cardiovascular including peripheral vasodilation, reduced peripheralresistance, and inhibition of baroreceptors; dermatologic includingpruritus (itching), flushing and red eyes; gastrointestinal includingnausea and vomiting, decreased gastric motility in stomach, decreasedbiliary, pancreatic and intestinal secretions and delays in fooddigestion in small intestine, diminished peristaltic waves in largeintestine contributing to constipation, epigastric distress or biliarycolic in biliary tract; respiratory including depressed respiratoryrate; and urinary including urinary urgency and difficulty withurination, and peripheral limb heaviness.

As used herein, “central nervous system effects” or “CNS effects”include, but are not limited to, narcosis, euphoria, drowsiness, apathy,psychotic ideation, mental confusion, alteration in mood, reduction inbody temperature, feelings of relaxation, dysphoria (an emotional statecharacterized by anxiety, depression, or unease), nausea and vomiting(caused by direct stimulation of chemoreceptors in the medulla).

As used herein, “mucosal administration” or “administeredtransmucosally” refers to delivery to the mucosal surfaces of the nose,nasal passageways, nasal cavity; the mucosal surfaces of the oral cavityincluding the gingiva (gums), the floor of the oral cavity, the cheeks,the lips, the tongue, the teeth; and the mucosal surfaces of or aroundthe eye including the conjunctiva, the lacrimal gland, the nasolacrimalducts, the mucosa of the upper or lower eyelid and the eye.

As used herein, “intranasal administration” or “administeredintranasally” refers to delivery to the nose, nasal passageways or nasalcavity by spray, drops, powder, gel, film, inhalant or other means.

The nasal cavity contains turbinate bones which protrude into the nasalcavity and generally separate it into three regions. As used herein, the“inferior region of the nasal cavity” refers to the portion of the nasalcavity where the middle and inferior turbinate bones protrude and is aregion of the nasal cavity that is innervated by the trigeminal nervesystem. The superior area of the nasal cavity is defined by the superiorturbinate bone wherein the olfactory region is located.

As used herein, “transdermal administration” or “dermal administration”refers to delivery to the skin including the face, neck, scalp, body orcombinations thereof. As used herein, dermal administration can includeintradermal or subcutaneous administration by various means such as aninjection.

As used herein, “pharmaceutically acceptable carrier” or “suitablecarrier” refers to a carrier that is conventionally used in the art tofacilitate the storage, administration, and/or the healing effect of theagent.

As used herein, “therapeutically effective dose”, “therapeuticallyeffective amount” or “an effective amount” refers to an amount of ananalgesic agent that is useful for treating pain.

As used herein, “prophylactically effective dose”, “prophylacticallyeffective amount” or “an effective amount” refers to an amount of ananalgesic agent that is useful for preventing pain.

As used herein, “visual analogue scale” or “VAS” refers to a commonlyused scale in pain assessment. It is a 10 cm horizontal or vertical linewith word anchors at each end, such as “no pain” and “worst painimaginable”. A subject or patient is asked to make a mark on the line torepresent pain intensity. This mark is converted to distance in eithercentimeters or millimeters from the “no pain” anchor to give a painscore that can range from 0-10 cm or 0-100 mm. The VAS may refer to an11 point numerical pain rating scale wherein 0 equals “no pain” and 10equals the “worst pain imaginable”.

It should be noted that, as used herein, the singular form “a”, “an”,and “the” includes plural references unless indicated otherwise.Additionally, as used herein, the term “comprising” and its cognates areused in their inclusive sense; that is, equivalent to the term“including” and its corresponding cognates.

Active Agents

Oxytocin was one of the first peptide hormones to be isolated andsequenced. It is a nine amino acid cyclic peptide hormone with twocysteine residues that form a disulfide bridge between positions 1 and6. The amino acid sequence for human oxytocin isCys-Tyr-Ile-Gln-Asn-Cys-Pro-Leu-Gly (SEQ ID NO:1). Oxytocin is releasedfrom the posterior lobe of the pituitary gland and stimulates thecontraction of smooth muscle of the uterus during labor and facilitatesrelease of milk from the breast during nursing. Studies have shown thatoxytocin may exert a wide spectrum of other biological effects includingcontrol of memory and learning processes, and various types of maternaland sexual behavior. In addition, oxytocin may participate in thecontrol of cardiovascular functions, thermoregulation and fluid balance.Other studies have shown that oxytocin can play an important role innociceptive modulation. Oxytocin is approved by the Food and DrugAdministration for intravenous use to induce labor in pregnant women aswell as for the treatment of postpartum hemorrhage. Oxytocin has notbeen previously used for treatment and/or prevention of headache orheadache disorders.

The oxytocin peptide for use in the methods described herein can benatural or synthetic, therapeutically or prophylactically active,peptide fragments, peptide analogues, and chemically modifiedderivatives or salts of active peptides. There are processes describedfor the production of oxytocin, see for example U.S. Pat. No. 2,938,891and U.S. Pat. No. 3,076,797; in addition, oxytocin is commerciallyavailable. A variety of peptide analogues and derivatives are availableand others can be contemplated for use within the invention and can beproduced and tested for biological activity according to known methods.Oxytocin analogues may included, but are not limited to,4-threonine-1-hydroxy-deaminooxytocin, 4-serine, 8-isoleucine-oxytocin,9-deamidooxytocin, 7-D-proline-oxytocin and its deamino analog,(2,4-diisoleucine)-oxytocin, deamino oxytocin analog,1-deamino-1-monocarba-E12-Tyr(OMe)]-OT(dCOMOT), carbetocin, 4-threonine,7-glycine-oxytocin (TG-OT), oxypressin, deamino-6-carba-oxytoxin (dC60),L-371,257 and the related series of compounds containing anortho-trigluoro-ethoxyphenylacetyl core such as L-374,943. Peptides foruse within the invention can be peptides that are obtainable by partialsubstitution, addition, or deletion of amino acids within a naturallyoccurring or native peptide sequence. Peptides can be chemicallymodified, for example, by amidation of the carboxyl terminus (—NH₂), theuse of D amino acids in the peptide, incorporation of small non-peptidylmoieties, as well as the modification of the amino acids themselves(e.g. alkylation or esterification of side chain R-groups). Suchanalogues, derivatives and fragments should substantially retain thedesired biological activity of the native oxytocin peptide.

All peptides described and/or contemplated herein can be prepared bychemical synthesis using either automated or manual solid phasesynthetic technologies, generally known in the art. The peptides canalso be prepared using molecular recombinant techniques known in theart.

In some aspects of the invention, an oxytocin peptide is administered incombination with at least one additional active agent. Additional activeagents may include, but are not limited to, non-peptide opioids, such asmorphine, methadone, fentanyl, butorphanol, codeine, opium, oxycodone,loperimide, meperidine (Demerol), diphenoxylate, propoxyphene (Darvon),4-methyl fentanyl, hydrocodone, morphine, diacetylmorphine,dihydrocodeine, hydromorphone (Dilaudid), levorphanol (Levo-Dromoran),dextromethorphan, oxymorphone (Numorphan), heroin, remifentanil,phenazocine, pentazocine, piminodine, anileridine, buprenorphine(Suboxone), sufentanil, carfentanil, alfentanil and the atypicalopiates, tramadol and tapentadol; opioid and opioid-like peptides andtheir analogs, such as endorphins, enkephalins, dynorphins, dermorphins,dermenkephalins, morphiceptin, endomorphins and dalargin; NMDA-receptorantagonists, such as ketamine, amantadine, dextrometorphane, memantineand MK801; sodium channel blockers, such as local anesthetics andergotamine; calcium channel blockers, such as verapamil and nifedipine;adrenergic antagonists, such as propranolol, metoprolol and yohimine;gabaergic agonists, such as GABA, baclofen, cis-4-aminocrotonic acid(CACA), trans-4-aminocrotonic acid (TACA), CGP 27 492 (3-aminopropylphosphonous acid) and progabide; glycine agonists, such as glycine andD-cycloserine; cholinergic agonists, such as neostigmine andphysiostigmine; adrenergic agonists, such as epinephrine, neosynephrine,clonidine and dexmedetomidine; anticonvulsants, such as gabapentin andbarbiturates; Rho kinase inhibitors, such as fasudil, Y27632, H-1152 andderivatives thereof; PKC inhibitors, such as chelerythrine, Gö 6983, Gö6976, N-myristoyl-Ser-Ile-Tyr-Arg-Arg-Gly-Ala-Arg-Arg-Trp-Arg-Lys-Leu,Rottlerin, KAI-9803 and KAI-1455; p38-MAP kinase inhibitors, such asSCIO-469, AMG548 and derivatives thereof; ATP receptor blockers, such astetramethylpyrazine chelerythrine chloride, A-317491 and derivativesthereof; endothelin receptor blockers, such as BQ123, BMS182874 andderivatives thereof; pro-inflammatory cytokine, chemokine, interleukinand tumor necrosis factor blockers, such as anakinra, infliximab,etanercept and adalimumab; anti-inflammatory cytokines, such asinterleukin-4, interleukin-10 and interleukin-13; tricyclicantidepressants, such as desiprimine and amitryptiline; serotonergicantagonists, such as fluoxetine, dolasetron and ondansetron;serotonergic agonists, such as buspirone and ergometrine; NSAIDs andCOXIBs, such as diclofenac, ibuprofen, ketorolac, salicylate, rofecoxib,celecoxib, parecoxib, valdecoxib and naproxen; acetaminophen; analgesicpeptides, such as calcitonin, octreotide, somatostatin, vasopressin,galanin, the C-fragment of lipotropin and Ac-rfwink-NH₂; toxins, such asbotulinum toxin, variants and derivatives thereof, cone snail toxins,such as omega-conotoxin GV1A, omega-conotoxin MVIIA, saxitoxin andtetrodotoxin; TRP channel agonists and antagonists, such as capsaicin,capsazepine, resiniferotoxin, SB-705498, A-425619, AMG 517, SC0030 andderivatives thereof; cannabanoids, such as THC, CT-3, levonantradol,dexanabinol, WIN-55, 212-2, AM 1241, dronabinol, nabilone, cannabismedicinal extract (CME) and derivatives thereof; antagonists ofpro-nociceptive peptide neurotransmitter receptors CGRP1 and CGRP2,including non-peptide antagonists such as BIBN4096 and derivativesthereof and peptide antagonists such as CGRP 8-37 and CGRP 28-3;antagonists of pro-nociceptive peptide neurotransmitter receptor NK1,including non-peptide antagonists such as SR140333, CP96346, L-760735;RP 67580, WIN 51708; MK869, and derivatives thereof and peptideantagonists such as N-acetyl tryptophan,D-Pro9-[Spiro-y-lactam]-Leu10,Trp11-Physalaemin(1-11),Tyr-D-Phe-Phe-D-His-Leu-Met-NH₂ (Sendide) and spantide II; antagonistsof pro-nociceptive peptide neurotransmitter receptor NK2, includingnon-peptide antagonists such as SR 48968 and derivatives thereof andpeptide antagonists such as PhCO-Ala-Ala-D-Trp-Phe-D-Pro-Pro-Nle-NH₂(GR98400), [Tyr5,D-Trp-6,8,9,Lys10]-NKA (4-10) (MEN10376) andderivatives thereof; antagonists of pro-nociceptive peptideneurotransmitter receptor Y1-5, including non-peptide antagonistbenextramine and peptide antagonists(Ile-Glu-Pro-Dpr-Tyr-Arg-Leu-Arg-Tyr-NH₂)₂, cyclic (2,4′),(2′,4)-diamide(1229U91 or GW1229), PYX-2, D-Tyr (27,36), D-Thr (32)1 NPY (27-36)(D-NPY(27-36),3-(5,6,7,8-tetrahydro-9-isopropyl-carbazol-3-yl)-1-methyl-1-(2-pyridin-4-yl-ethyl)-ureahydrochloride (FMS586 and derivatives thereof); antagonists ofpro-nociceptive peptide neurotransmitter receptors VPAC2, VPAC1 andPAC1, including peptide antagonists VIP(6-28), Ac His(1) [D-Phe(2),K(15), R(16), L(27)] VIP (3-7)/GRF (8-27); antagonists ofpro-nociceptive peptide neurotransmitter receptors Gal1-3 and GalR1-3,including non-peptide antagonists SNAP 37889, SNAP 398299, galnon andderivatives thereof. Additional active agents may include agonists orantagonists of vasopressin, corticotropin releasing hormone (CRH),growth hormone releasing hormone (GHRH), luteinizing hormone releasinghormone (LHRH), somatostatin growth hormone release inhibiting hormone,thyrotropin releasing hormone (TRH), glial-derived neurotrophic factor(GDNF), brain-derived neurotrophic factor (BDNF), nerve growth factor(NGF), neurotrophin-3 (NT-3), pancreatic polypeptide, peptidetyrosine-tyrosine, glucogen-like peptide-1 (GLP-1), peptide histidineisoleucine (PHI), pituitary adenylate cyclase activating peptide(PACAP), brain natriuretic peptide, cholecystokinin (CCK), islet amyloidpolypeptide (IAPP) or amylin, melanin concentrating hormone (MCH),melanocortins (ACTH, α-MSH and others), neuropeptide FF (F8Fa),neurotensin, parathyroid hormone related protein, Agouti gene-relatedprotein (AGRP), cocaine and amphetamine regulated transcript(CART)/peptide, 5-HT-moduline, hypocretins/orexins, nociceptin/orphaninFQ, ocistatin, prolactin releasing peptide, secretoneurin, urocortin andderivatives and analogues thereof.

Accordingly, described herein are methods for the treatment of headachepain or trigeminal neuralgia in an individual comprising administeringto the individual an effective amount of an oxytocin peptide. Ingeneral, the methods administer an oxytocin peptide for prevention ortreatment of head pain. In some aspects the head pain is a result ofprimary and secondary headaches. In some examples the primary headacheis a vascular headache or a tension-type headache. In some examples thevascular headache is a migraine or a cluster type headache. In otherexamples, the head pain is a result of trigeminal neuralgia. Someaspects of the invention include methods wherein the administrationresults predominantly in analgesia to the facial or head region and inalleviation of headache pain. Some aspects of the invention includemethods wherein an oxytocin peptide is administered prior to headachepain for preventive treatment. In other aspects of the invention anoxytocin peptide is administered in combination with at least oneadditional active agent.

Administration

Described herein are methods for the treatment of headache pain ortrigeminal neuralgia in an individual comprising administering to theindividual an oxytocin peptide to mucosa tissue or epithelium within theoral cavity, the nasal cavity, within or around the eye or to the skin.The oral mucosal tissues include, but are not limited to, the gingiva(gums), the floor of the oral cavity, the cheeks, the lips, the tongue,the teeth or a combination thereof. The methods can includeadministering an oxytocin peptide to conjunctiva or other mucosaltissues around the eye. The tissues or epithelium include, but are notlimited to, the conjunctiva, the lacrimal gland, the nasolacrimal ducts,the mucosa of the upper or lower eyelid, the eye, or a combinationthereof. An oxytocin peptide that is administered to the conjunctiva butnot absorbed completely through the conjunctival mucosa can drainthrough the nasolacrimal ducts into the nose wherein it can be absorbedby mucosal tissue within the nasal cavity. An oxytocin peptide can beadministered to the mucosa tissue within the nasal cavity. Suitableregions include, but are not limited to, the inferior two-thirds of thenasal cavity.

Intranasal drug delivery has been a topic of research and developmentfor many years, although it has been only within the past decade thatcarrier systems have been devised which make delivery of substanceseffective. (Sayani and Chien (1996) Critical Reviews in Therapeutic DrugCarrier Systems, 13:85-184.) Intranasal delivery has a number ofadvantageous features including comparatively high bioavailability,rapid kinetics of absorption and avoidance of a first-pass effect in theliver. In regard to patient compliance and ease of use, intranasaladministration provides a simple, rapid and non-invasive mode ofapplication. In some aspects, intranasal administration can allow fordelivery of an oxytocin peptide to the nasal cavity and in otheraspects, intranasal administration can allow for targeted delivery tothe trigeminal nerve. Targeted delivery to the trigeminal nerve andpreferably not the olfactory region can reduce the amount of drugentering the CNS or systemic circulation thereby reducing or eliminatingpotential undesirable CNS effects or systemic side effects. Targeteddelivery to the trigeminal nerve can also reduce the effective dosagenecessary to achieve analgesia in the facial or head regions whereinlower effective dosages will further reduce any potential CNS orsystemic side effects.

Some aspects of the present invention include methods for treatment ofheadache pain or trigeminal neuralgia in an individual comprisingadministering to the individual an oxytocin peptide by intranasaladministration. In some examples the pain is associated with a migraine.In other examples the pain is associated with a cluster headache. In yetother examples the pain is associated with a tension-type headache. Inyet other examples the pain is associated with trigeminal neuralgia.

Some aspects of the present invention include methods for prevention ofheadache pain or trigeminal neuralgia in an individual comprisingadministering to the individual an oxytocin peptide by intranasaladministration. In some examples the individual is experiencing amigraine-associated aura and the individual is administered an oxytocinpeptide prior to the onset of a migraine headache. In other examples anindividual is experiencing a series of cluster headaches and theindividual is administered an oxytocin peptide after the cluster serieshas started to prevent or decrease the intensity or frequency ofsuccessive headaches in the series. In other examples the individual isexperiencing bursts of pain from a trigeminal neuralgia attack and theindividual is administered an oxytocin peptide to prevent furtherattacks.

Some aspects of the present invention include methods for treatment ofheadache pain or trigeminal neuralgia in an individual comprisingadministering to the individual an oxytocin peptide by intranasaladministration wherein the administration results predominantly inanalgesia to the facial or head region and in alleviation of headachepain. In some examples, the methods can administer an oxytocin peptideto the nasal cavity of an individual, in particular to the inferiorregion of the nasal cavity, to promote delivery to the trigeminal nervewith minimal delivery to the olfactory nerve.

Within the oral cavity, the buccal or sublingual delivery routes areconvenient choices for drug delivery as they are user-friendly andnon-invasive. Some of the advantages include i) less proteolyticactivity in the oral cavity as compared to some other routes therebyavoiding the problems of enzymatic degradation of peptide and proteindrugs and ii) bypassing the liver first pass effect. Drug delivery tothe mucosal tissue around the eye or to the conjunctiva is anotherconvenient choice for drug delivery that is non-invasive.

Some aspects of the present invention include methods for treatment ofheadache pain or trigeminal neuralgia in an individual comprisingadministering an effective amount of an oxytocin peptide to theconjunctiva or other mucosal tissues around the eye.

Transdermal drug delivery or administration of a therapeutic agent tothe skin has become a proven technology over the last 20 years.Transdermal drug delivery offers controlled release of a drug to thepatient and transdermal patches are user-friendly, convenient, painless,and offer multi-day dosing which usually results in improved patientcompliance. The methods can include administering an oxytocin peptide toskin of the face, head or body. An oxytocin peptide can be administeredto the skin of the face, scalp or temporal region. Suitable skin of theface includes skin of the chin, the upper lip, the lower lip, theforehead, the nose, the cheek, the skin around the eyes, the uppereyelid, the lower eyelid or combinations thereof. Suitable skin of thescalp includes the front of the scalp, the scalp over the temporalregion, the lateral part of the scalp, or combinations thereof. Suitableskin of the temporal region includes the temple and the scalp over thetemporal region and combinations thereof.

Intradermal administration of a therapeutic agent is defined as withinor between the layers of skin. In contrast, subcutaneous administrationis defined as beneath the initial layer of skin. Administration oftherapeutic agents by intradermal or subcutaneous injection are commonmeans of drug delivery by one skilled in the art.

In some aspects of the invention a vasoconstrictor is used to decreasesystemic uptake of an oxytocin peptide. The vasoconstrictor can beincluded in a pharmaceutical composition to decrease systemic uptake ofthe oxytocin peptide. Alternatively, the vasoconstrictor may bedelivered to the mucosal or dermal surface separately from thepharmaceutical composition. Vasoconstrictors are compounds thatconstrict blood vessels and capillaries and decrease blood flow. Theycan be used to increase concentration of an agent at a desired site byinhibiting movement of the agent into the bloodstream and therebyreducing systemic uptake and distribution of the agent. Vasoconstrictorscan be used to decrease the effective dosage of an agent needed toachieve analgesia by limiting systemic distribution and concentratingthe agent in a localized area, i.e. the facial and head regions.Accordingly, a vasoconstrictor can be administered before administrationof an oxytocin peptide or can be co-administered with an oxytocinpeptide. Vasoconstrictors may include, but are not limited to,phenylephrine hydrochloride, tetrahydrozoline hydrochloride, naphazolinenitrate, oxymetazoline hydrochloride, tramazoline hydrochloride,ergotamine, dihydroergotamine, endothelin-1, endothelin-2, epinephrine,norepinephrine and angiotensin.

Some aspects of the present invention include methods wherein avasoconstrictor is administered to the nasal cavity of an individualprior to administration of an oxytocin peptide, wherein administrationof the vasoconstrictor decreases systemic distribution of the oxytocinpeptide. In some examples, the methods can co-administer avasoconstrictor and an oxytocin peptide to the nasal cavity of anindividual, wherein administration of the vasoconstrictor decreasessystemic distribution of the oxytocin peptide. In other examples, themethods can administer a vasoconstrictor to the nasal cavity of anindividual prior to or co-administer with an oxytocin peptide, whereinadministration of the vasoconstrictor decreases systemic uptake anddistribution of the oxytocin peptide thereby decreasing the effectivedosage requirement of the oxytocin peptide necessary to achieveanalgesia in the facial or head region and to alleviate headache pain ortrigeminal neuralgia pain.

In some aspects of the present invention administration of an oxytocinpeptide targeted for a predominantly regional analgesic effect canresult in prevention or alleviation of headache pain or trigeminalneuralgia without numbness as compared to local anesthetics or thestrong sedative effect associated with narcotic type drugs. Since thetrigeminal nerve transmits most of the sensory signals of the face andhead, administration of an oxytocin peptide targeted to the trigeminalnerve can localize the analgesic effect to the face and head region.Targeted delivery can also decrease the amount of oxytocin peptideadministered to an individual to achieve an analgesic effect, and candecrease any potential undesirable CNS effects or systemic side effects.More effective or efficient delivery of an oxytocin peptide to thetrigeminal nerve can decrease the total dose of the peptide administeredto a subject suffering from headache pain or trigeminal neuralgia.Effective targeted delivery of an oxytocin peptide to the trigeminalnerve can decrease the systemic distribution of the agent wherein anypotential undesirable CNS effects or systemic side effects are minimizedor eliminated.

Accordingly, provided herein are methods for treatment of headache painor trigeminal neuralgia in an individual comprising administering to theindividual an oxytocin peptide wherein the administration is targeted tothe trigeminal nerve system and results predominantly in analgesia tothe facial or head region as compared to analgesic effects in otherparts of the body and in alleviation of head pain.

Pharmaceutical Composition

While it is possible to administer an oxytocin peptide alone, there aresituations wherein it is advantageous to present it as part of apharmaceutical composition. Thus, in some aspects of the presentinvention, an oxytocin peptide is administered as a pharmaceuticalcomposition. The pharmaceutical composition can comprise an oxytocinpeptide at a therapeutically effective dose together with one or morepharmaceutically acceptable carriers and optionally other ingredients. Asuitable carrier is one which does not cause an intolerable side effect,but which allows oxytocin to retain its pharmacological activity in thebody. A carrier may also reduce any undesirable side effects ofoxytocin. A suitable carrier should be stable, i.e., incapable ofreacting with other ingredients in the formulation. A suitable carriershould have minimal odor or fragrance or fragrance or a positive(pleasant) odor. A suitable carrier should not irritate the mucosa,epithelium, underlying nerves or provide a health risk. It may be anaccepted transcutaneous or percutaneous carrier or vehicle, because anycarrier that can effectively penetrate the stratum corneum of the skinshould be highly efficacious in not only penetrating mucosa, but alsoallowing rapid absorption of substances into the submucosal tissues,nerve sheaths and nerves.

Suitable nontoxic pharmaceutically acceptable carriers will be apparentto those skilled in the art of pharmaceutical formulations. Also seeRemington: The Science and Practice of Pharmacy, 20th Edition,Lippincott, Williams & Wilkins (2000). Typical pharmaceuticallyacceptable carriers include, but are not limited to, mannitol, urea,dextrans, lactose, potato and maize starches, magnesium stearate, talc,vegetable oils, polyalkylene glycols, ethyl cellulose,poly(vinylpyrrolidone), calcium carbonate, chitosan, ethyl oleate,isopropyl myristate, benzyl benzoate, sodium carbonate, gelatin,potassium carbonate, silicic acid, and other conventionally employedacceptable carriers. Other carriers include, but are not limited to,phosphatidylcholine, phosphatidylserine, and sphingomyelins.

The choice of a suitable carrier will depend on the exact nature of theparticular formulation desired, e.g., whether the drug is to beformulated into a liquid solution (e.g., for use as drops, for use in aninjection, as a spray or impregnated in a nasal tampon, or otheragent-impregnated solid), a suspension, a ointment, a film or a gel. Ifdesired, sustained-release compositions, e.g. sustained-release gels,films, transdermal patchs, etc. can be readily prepared. The particularformulation will also depend on the route of administration. The agentcan be administered to the nasal cavity as a powder, a granule, asolution, a cream, a spray, a gel, a film, an ointment, an infusion, adrop or a sustained-release composition. For buccal administration, thecomposition can take the form of tablets or lozenges formulated in aconvention manner. For sublingual administration, the composition cantake the form of a bioadhesive, a spray, a powder, paint or a swabapplied to or under the tongue. For administration to the conjunctiva orother mucosal tissues around the eye, the composition can be applied asan ointment, a solution or a drop. For administration to the skin, thecomposition can be applied as a topical ointment, a topical gel, alotion, a cream, a solution, a spray, a paint, a film, a foil, acosmetic, a patch or a bioadhesive.

Liquid carriers include, but are not limited to, water, saline, aqueousdextrose, and glycols particularly (when isotonic) for solutions. Thecarrier can also be selected from various oils, including those ofpetroleum, animal, vegetable or synthetic origin, (e.g. peanut oil,soybean oil, mineral oil, sesame oil, and the like). Suitablepharmaceutical excipients include, but are not limited to, starch,cellulose, talc, glucose, lactose, sucrose, gelatin, malt, rice, flour,chalk, silica gel, magnesium stearate, sodium stearate, glycerolmonostearate, sodium chloride, dried skim milk, glycerol, propyleneglycol, water, ethanol, and the like. The compositions can be subjectedto conventional pharmaceutical processes, such as sterilization, and cancontain conventional pharmaceutical additives, such as preservatives,stabilizing agents, reducing agents, anti-oxidants, chelating agents,wetting agents, emulsifying agents, dispersing agents, jelling agents,salts for adjusting osmotic pressure, buffers, and the like. Where thecarrier is a liquid, it is preferred that the carrier be hypotonic orisotonic with body fluids and have a pH within the range of 4.5-8.5.Where the carrier is in powdered form, it is preferred that the carrierbe within an acceptable non-toxic pH range. The use of additives in thepreparation of peptide and/or protein-based compositions, particularlypharmaceutical compositions, is well-known in the art.

The lists of carriers and additives discussed herein are by no meanscomplete and a worker skilled in the art can choose carriers andexcipients from the GRAS (generally regarded as safe) list of chemicalsallowed in pharmaceutical preparations and those that are currentlyallowed in topical and parenteral formulations. (See also Wang et al.,(1980) J. Parent. Drug Assn., 34:452-462; Wang et al., (1988) J. Parent.Sci. and Tech., 42:S4-S26.)

Other forms of compositions for administration include a suspension of aparticulate, such as an emulsion, a liposome, or in a sustained-releaseform to prolong the presence of the pharmaceutically active agent in anindividual. The powder or granular forms of the pharmaceuticalcomposition may be combined with a solution and with a diluting,dispersing or surface-active agent. Additional compositions foradministration include a bioadhesive to retain the agent at the site ofadministration, for example a spray, paint, or swab applied to themucosa or epithelium. A bioadhesive can refer to hydrophilic polymers,natural or synthetic, which, by the hydrophilic designation, can beeither water soluble or swellable and which are compatible with thepharmaceutical composition. Such adhesives function for adhering theformulations to the mucosal tissues of the oral or nasal cavity. Suchadhesives can include, but are not limited to, hydroxypropyl cellulose,hydroxypropyl methylcellulose, hydroxy ethylcellulose, ethylcellulose,carboxymethyl cellulose, dextran, gaur gum, polyvinyl pyrrolidone,pectins, starches, gelatin, casein, acrylic acid polymers, polymers ofacrylic acid esters, acrylic acid copolymers, vinyl polymers, vinylcopolymers, polymers of vinyl alcohols, alkoxy polymers, polyethyleneoxide polymers, polyethers, and combinations thereof. The compositioncan also be in the form of lyophilized powder, which can be convertedinto solution, suspension, or emulsion before administration. Thepharmaceutical composition is preferably sterilized by membranefiltration and is stored in unit-dose or multi-dose containers such assealed vials or ampoules.

The pharmaceutical composition can be formulated in a sustained-releaseform to prolong the presence of the active agent in the treatedindividual. Many methods of preparation of a sustained-releaseformulation are known in the art and are disclosed in Remington'sPharmaceutical Sciences (see above). Generally, the agent can beentrapped in semi-permeable matrices of solid hydrophobic polymers. Thematrices can be shaped into films or microcapsules. Matrices caninclude, but are not limited to, polyesters, co-polymers of L-glutamicacid and gamma ethyl-L-glutamate, polylactides, polylactatepolyglycolate, hydrogels, non-degradable ethylene-vinyl acetate,degradable lactic acid-glycolic acid copolymers, hyaluronic acid gels,and alginic acid suspensions. Suitable microcapsules can also includehydroxymethylcellulose or gelatin and poly-methyl methacrylate.Microemulsions or colloidal drug delivery systems such as liposomes andalbumin microspheres can also be used. Some sustained-releasecompositions can use a bioadhesive to retain the agent at the site ofadministration.

To further enhance the mucosal delivery of a pharmaceutical compositioncomprising an oxytocin peptide, an enzyme inhibitor, particularlyproteases inhibitors, can be included in the formulation. Proteaseinhibitors may include, but are limited to, antipain, arphamenine A andB, benzamidine HCl, AEBSF, CA-074, calpain inhibitor I and II,calpeptin, pepstatin A, actinonin, amastatin, bestatin, boroleucine,captopril, chloroacetyl-HOLeu-Ala-Gly-NH₂, DAPT, diprotin A and B,ebelactone A and B, foroxymithine, leupeptin, pepstatin A,phosphoramidon, aprotinin, puromycin, BBI, soybean trypsin inhibitor,phenylmethylsulfonyl fluoride, E-64, chymostatin, 1,10-phenanthroline,EDTA and EGTA.

To enhance delivery into or across a mucosal surface and/or absorptionof a pharmaceutical composition comprising an oxytocin peptide, anabsorption-enhancing agent can be included in the formulation. Theseenhancing agents may enhance the release or solubility (e.g., from aformulation delivery vehicle), diffusion rate, penetration capacity andtiming, uptake, residence time, stability, effective half-life, peak orsustained concentration levels, clearance and other desired mucosaldelivery characteristics (e.g., as measured at the site of delivery) ofthe composition. Enhancement of mucosal delivery can thus occur by anyof a variety of mechanisms, for example by increasing the diffusion,transport, persistence or stability of an oxytocin peptide, increasingmembrane fluidity, modulating the availability or action of calcium andother ions that regulate intracellular or paracellular permeation,solubilizing mucosal membrane components (e.g., lipids), changingnon-protein and protein sulfhydryl levels in mucosal tissues, increasingwater flux across the mucosal surface, modulating epithelial junctionalphysiology, reducing the viscosity of mucus overlying the mucosalepithelium, reducing mucociliary clearance rates, and other mechanisms.

Mucosal absorption enhancing compounds may include, but are not limitedto, surfactants, bile salts, dihydrofusidates, bioadhesive agents,phospholipid additives, mixed micelles, liposomes, or carriers,alcohols, enamines, cationic polymers, NO donor compounds, long-chainamphipathic molecules, small hydrophobic penetration enhancers; sodiumor a salicylic acid derivatives, glycerol esters of acetoacetic acid,cyclodextrin or beta-cyclodextrin derivatives, medium-chain fatty acids,chelating agents, amino acids or salts thereof, N-acetylamino acids orsalts thereof, mucolytic agents, enzymes specifically targeted to aselected membrane component, inhibitors of fatty acid synthesis andinhibitors of cholesterol synthesis.

These additional agents and compounds can be coordinately administeredor combinatorially formulated with an oxytocin peptide. Accordingly,some aspects of the present invention include methods wherein anoxytocin peptide is administered as a pharmaceutical composition thatcomprises protease inhibitors, absorption enhancers, vasoconstrictors orcombinations thereof. The pharmaceutical composition can be administeredto the nasal cavity, oral cavity, to conjunctiva or other mucosaltissues around the eye or to the skin. The pharmaceutical compositioncan be administered by an intranasal route. The pharmaceuticalcomposition can be administered by a buccal or sublingual route. Thepharmaceutical composition can be administered by a transdermal route.The pharmaceutical composition can be administered by more than oneroute. The pharmaceutical composition can include at least one proteaseinhibitor, at least one absorption enhancer, at least onevasoconstrictor or combinations thereof. The pharmaceutical compositioncan be co-administered with a vasoconstrictor or administered after thevasoconstrictor has been delivered.

Delivery Systems

An oxytocin peptide or a pharmaceutical composition comprising anoxytocin peptide may be dispensed to the buccal or sublingual surfacesin a number of different formulations or dosage forms including, but notlimited to, fast-melting tablets, liquid-filled capsules, liquid spraysor lozenges. Alternatively, a pharmaceutical composition can bedelivered to the mucosa of the oral cavity by direct placement of thecomposition in the mouth, for example, with a gel, a film, an ointment,a dropper, or a bioadhesive strip or patch.

In some aspects of the present invention, the methods compriseadministering to an individual a pharmaceutical composition whereinadministration to the buccal and/or sublingual mucosal surfaces of theoral cavity is by a delivery device. The delivery device can include,but is not limited to, unit dose containers, pump sprays, droppers,squeeze bottles, airless and preservative-free sprays, nebulizers, doseinhalers and pressurized dose inhalers. The delivery device can bemetered to administer an accurate effective dosage amount (as describedbelow) to the oral cavity. In some aspects, an accurate effective dosageamount is contained within a capsule, tablet, lozenge, or bioadhesivepatch that is placed directly within the oral cavity.

An oxytocin peptide or a pharmaceutical composition comprising anoxytocin peptide may be dispensed to the conjunctiva or to other mucosaltissues around the eye in a number of different formulations such as aliquid drop, a gel, a film, an ointment or a bioadhesive patch or strip.Thus, in some aspects of the present invention the methods compriseadministering to an individual a pharmaceutical composition whereinadministration is directed to the conjunctiva or other mucosal tissuesaround the eye. In some aspects, an accurate effective dosage amount iscontained within a drop, a gel, a film, an ointment or a bioadhesivepatch that is placed directly onto the mucosal tissues around the eye.

An oxytocin peptide or pharmaceutical composition comprising an oxytocinpeptide may be administered to the skin or scalp in a number ofdifferent formulations such as a liquid, a spray, a gel, a film, anointment or a bioadhesive patch or strip. Thus, in some aspects of thepresent invention the methods comprise administering to an individual apharmaceutical composition wherein administration is directed to theskin of the face, scalp or body. In some aspects, an accurate effectivedosage amount is contained within a drop, a gel, a film, an ointment ora bioadhesive transdermal patch that is placed directly onto the skin.In some aspects, a pharmaceutical composition may be administered to theskin intradermally by injection. In other aspects the composition may beadministered to the skin subcutaneously by injection.

An oxytocin peptide or a pharmaceutical composition comprising anoxytocin peptide may be dispensed intranasally as a powdered or liquidnasal spray, suspension, nose drops, a gel, film or ointment, through atube or catheter, by syringe, by packtail, by pledget (a small flatabsorbent pad), by nasal tampon or by submucosal infusion. Nasal drugdelivery can be carried out using devices including, but not limited to,unit dose containers, pump sprays, droppers, squeeze bottles, airlessand preservative-free sprays, nebulizers (devices used to change liquidmedication to an aerosol particulate form), metered dose inhalers, andpressurized metered dose inhalers. It is important that the deliverydevice protect the drug from contamination and chemical degradation. Thedevice should also avoid leaching or absorption as well as provide anappropriate environment for storage. Each drug needs to be evaluated todetermine which nasal drug delivery system is most appropriate. Nasaldrug delivery systems are known in the art and several are commerciallyavailable.

An oxytocin peptide or a pharmaceutical composition comprising anoxytocin peptide may be conveniently delivered in the form of an aerosolspray using a pressurized pack or a nebulizer and a suitable propellantincluding, but not limited to, dichlorodifluoromethane,trichlorofluoromethane, dichlorotetrafiuoroethane, hydrocarbons,compressed air, nitrogen or carbon dioxide. An aerosol system requiresthe propellant to be inert towards the pharmaceutical composition. Inthe case of a pressurized aerosol, the dosage unit may be controlled byproviding a valve to deliver an accurately metered amount.

The means to deliver an oxytocin peptide or pharmaceutical compositioncomprising an oxytocin peptide to the nasal cavity as a powder can be ina form such as microspheres delivered by a nasal insufflator device (adevice to blow a gas, powder, or vapor into a cavity of the body) orpressurized aerosol canister. The insufflator produces a finely dividedcloud of the dry powder or microspheres. The insufflator may be providedwith means to ensure administration of a substantially metered amount ofthe pharmaceutical composition. The powder or microspheres should beadministered in a dry, air-dispensable form. The powder or microspheresmay be used directly with an insufflator which is provided with a bottleor container for the powder or microspheres. Alternatively the powder ormicrospheres may be filled into a capsule such as a gelatin capsule, orother single dose device adapted for nasal administration. Theinsufflator can have means such as a needle to break open the capsule orother device to provide holes through which jets of the powderycomposition can be delivered to the nasal cavity.

Nasal delivery devices can be constructed or modified to dispense anoxytocin peptide or a pharmaceutical composition comprising an oxytocinpeptide wherein the oxytocin peptide or the composition is deliveredpredominantly to the inferior two-thirds of the nasal cavity. Forexample, the angle of dispersion from a delivery device such as anebulizer or an insufflator can be set so that the pharmaceuticalcomposition is mechanically directed to the inferior two-thirds of thenasal cavity, and preferably away from the superior region of the nasalcavity. Alternatively, an oxytocin peptide or a pharmaceuticalcomposition comprising an oxytocin peptide can be delivered to theinferior two-thirds of the nasal cavity by direct placement of thecomposition in the nasal cavity, for example, with a gel, an ointment, anasal tampon, a dropper, or a bioadhesive strip.

Thus in some aspects of the present invention, the methods compriseadministering to an individual an oxytocin peptide or pharmaceuticalcomposition comprising an oxytocin peptide wherein administration to thenasal cavity is by a nasal delivery device. The nasal delivery devicecan include, but is not limited to, unit dose containers, pump sprays,droppers, squeeze bottles, airless and preservative-free sprays,nebulizers, dose inhalers, pressurized dose inhalers, insufflators, andbi-directional devices. The nasal delivery device can be metered toadminister an accurate effective dosage amount (as described below) tothe nasal cavity. The nasal delivery device can be for single unitdelivery or multiple unit delivery. In some aspects of the presentinvention, the nasal delivery device can be constructed whereby theangle of dispersion of a pharmaceutical composition is mechanicallydirected towards the inferior two-thirds of the nasal cavity therebyminimizing delivery to the olfactory region. In some aspects of thepresent invention, the nasal delivery device may be activated only onexhalation, thus limiting the inhalation induced and potentiallyundesirable distribution of the pharmaceutical composition. In someaspects of the present invention, the pharmaceutical composition is agel, film, cream, ointment, impregnated in a nasal tampon or bioadhesivestrip whereby the composition is placed in the inferior two-thirds ofthe nasal cavity. In some aspects of the present invention, the methodsinclude intranasal administration of an oxytocin peptide or apharmaceutical composition comprising an oxytocin peptide wherein theadministration uses a nasal delivery device with an angle of dispersionthat mechanically directs the agent to the inferior two-thirds of thenasal cavity wherein the oxytocin peptide is administered after avasoconstrictor. In some aspects of the present invention, the methodsinclude intranasal administration of an oxytocin peptide orpharmaceutical composition comprising an oxytocin peptide wherein theadministration uses a nasal delivery device with an angle of dispersionthat mechanically directs the agent to the inferior two-thirds of thenasal cavity wherein the oxytocin peptide is co-administered with avasoconstrictor.

Dosages

An oxytocin peptide is administered in a dose sufficient to provide atherapeutically effective amount to an individual suffering fromheadache pain or trigeminal neuralgia. In some aspects, an oxytocinpeptide can be administered in a dose that results in analgesia to thefacial or head regions with minimal global CNS effects or systemic sideeffects. A therapeutically effective dose of an oxytocin peptide can bedetermined empirically and depends on the type and severity of theheadache pain, the route of administration, and the size, weight, ageand overall health of the patient, as is within the skill of one in theart such as a medical practitioner.

The amount of an oxytocin peptide administered as a unit dose willdepend upon the type of pharmaceutical composition being administered,for example, a solution, a suspension, a gel, a film, an emulsion, apowder, or a sustained-release formulation. In some examples, theeffective dosage will be lower than dose amounts needed for oral,intravenous, intramuscular or subcutaneous administration, sincetransmucosal or transdermal delivery may allow for a more concentratedlevel of the oxytocin peptide within the facial and head region. Thequantity of formulation needed to deliver the desired dose will alsodepend on the concentration of the oxytocin peptide in the composition.Such determinations are within the skill of one in the art.

The therapeutic dosage of an oxytocin peptide in the pharmaceuticalcompositions used in the methods of the present invention will depend ona number of factors such as the chemical composition and/or modificationof the oxytocin peptide, its bioavailability by the chosen route ofadministration, its efficacy, the desired frequency of administrationcombined with the desired single dosage of the formulation and whetherthe oxytocin peptide is administered in combination with other activeagent(s). Particularly, the dosage of an oxytocin peptide will be chosento maximize alleviation of headache pain or trigeminal neuralgia.Pharmacological data can be obtained from animal models and clinicaltrials with normal human volunteers or patients experiencing headachepain or trigeminal neuralgia by one with skill in the art.

Experimental models to test for analgesic activity of agents are knownin the art. Animal models comprise tests which include, but are notlimited to, acetic acid writhing, phenylquinone writhing, tail-flick,paw withdrawal and ear/face withdrawal wherein the pain receptoractivation is induced by such compounds as acetic acid, phenylquinone,formalin or capsaicin, or by thermal activators such as a hot plate or alaser. In particular, models for facial or head pain utilizing testssuch as orofacial delivery of capsaicin, orofacial delivery of formalin,or delivery of thermal heat to the ear or the face are available. Modelscan be used to determine optimal dosage ranges wherein an analgesicagent results in analgesia in the facial or head region with minimalanalgesia at a systemic site, i.e. the paw. Further, models can be usedto administer an analgesic agent by a particular delivery route, e.g.intranasally, and test for analgesic effect at the ears or the face andat the hindpaws. Thus, one model can be used to test for analgesicactivity of an analgesic agent after administration of a pharmaceuticalcomposition wherein withdrawal latencies at the ear or face willdetermine localized analgesia while withdrawal latencies at the hindpawwill determine systemic distribution and analgesia.

As stated above, an effective amount of an oxytocin peptide will dependon the form and composition being used in the method. Preferably theeffective amount of an oxytocin peptide administered transmucosally ortransdermally is lower than dosages used when the agent is delivered byother routes (e.g. oral, intravenous, intramuscular or subcutaneous).For example, dosages used for administration of an oxytocin peptide caninclude, but are not limited to, an effective amount within the dosagerange of about 0.1 IU to about 150 IU, or within 1 IU to about 100 IU,or within 10 IU to about 80 IU, or within about 25 IU to about 50 IU, orwithin about 1 IU to about 40 IU, or within about 1 IU to about 30 IU,or within about 4 IU to about 16 IU, or within about 4 IU to about 24IU.

Dosages can be administered in a single dose or in multiple doses, forexample, dosages can be administered two, three, four, up to ten timesdaily depending on the type and severity of headache pain being treatedas well as on individual susceptibility. Dosages can be administered ina sustained release formulation which may allow for an oxytocin peptideto be administered less frequently such as six times a week, five timesa week, four times a week, three times a week, twice a week, or once aweek.

Thus some aspects of the present invention include methods for treatmentof headache pain or trigeminal neuralgia comprising administering to anindividual an effective amount of an oxytocin peptide. The oxytocinpeptide can be administered within a dosage range of about 0.1 IU toabout 150 IU, or within 0.1 IU to about 100 IU, or within 1 IU to about100 IU, or within 10 IU to about 80 IU, or within about 25 IU to about50 IU, or within about 1 IU to about 40 IU, or within about 1 IU toabout 30 IU, or within about 4 IU to about 16 IU, or within about 4 IUto about 24 IU. In some examples the oxytocin peptide is administered ina dose of about 4 IU. In some examples, the dose is about 8 IU. In otherexamples the dose is about 16 IU. In some examples, the dose is about 24IU.

In some aspects of the present invention, a composition comprising anoxytocin peptide may further comprise an additional active agent,wherein the oxytocin peptide and the additional active agent(s) areadministered as a mixture, separately and simultaneously, or separatelyin any order. In some examples the composition comprising an oxytocinpeptide is administered in combination with at least one additionalactive agent. In other examples, the composition comprising an oxytocinpeptide is administered in combination with at least two additionalactive agents. In other example, the composition comprises an oxytocinpeptide administered in combination with diclofenac.

To determine the therapeutic effect of an oxytocin peptide or acomposition comprising an oxytocin peptide, the “visual analogue scale”(VAS) may be used to assess the reduction or alleviation of pain afteradministration of the oxytocin. VAS is a 10 cm horizontal or verticalline with word anchors at each end, such as “no pain” and “pain as badas it could be”. A subject or patient is asked to make a mark on theline to represent pain intensity. This mark is converted to distance ineither centimeters or millimeters from the “no pain” anchor to give apain score that can range from 0-10 cm or 0-100 mm. The VAS may also beset up as an 11 point numerical pain rating scale wherein 0 equals “nopain” and 10 equals the “worst pain imaginable”. Using the VAS, ananalgesic agent, e.g. oxytocin, is considered to have an analgesiceffect when there is a change of about 30% or more, for example a changefrom 9 to 7 or from 5 to 3.5.

Therapeutic Uses

Head pain can arise from a variety of medical conditions including butnot limited to, primary headaches such as migraine, cluster headache,tension or stress headache, secondary headaches caused by specificconditions such as neoplastic and infectious diseases, toxin ingestionor over-consumption of alcohol and trigeminal neuralgia. As discussedherein, the most common type of primary vascular headache is migrainewith cluster headache being less common but equally debilitating.Tension or “stress”-type headaches are believed to be the most commonheadache type overall in regard to affecting the largest number ofindividuals. The characteristics of these headaches or headachedisorders are summarized in Table 1.

TABLE 1 Trigeminal Migraine Tension Cluster Neuralgia PathophysiologyTrigemino- Myo-facial Trigemino- Trigeminal vascular pathway autonomicnerve pathway pathway pathway Laterality Unilateral Bilateral UnilateralUnilateral (60%) (100%) Intensity Moderate to Mild to Severe Severesevere Moderate Pain Pulsating (50%) Pressing Boring, piercing StabbingCharacteristic Electric shock-like Duration 4-72 hours Minutes to days15-180 minutes 1-2 seconds to Several per a 2 minutes day Many per a dayPhysical Aggravated by No effect Patients are Minor Activity Effectactivity restless movements can bring on attack Associated NauseaConjuctival Symptoms Photophobia injection Phonophobia Lacrimation Nasalcongestion Rhinorrhea Facial sweating Miosis Ptosis Eyelid edema

Headache pain and trigeminal neuralgia are often not effectively treatedwith current medications and new methods for pain relief are needed.Accordingly, some aspects of the present invention include methods fortreatment of headache pain or trigeminal neuralgia by administration ofan effective amount of an oxytocin peptide wherein the administrationresults in analgesia to the facial or head region. The oxytocin peptidecan be administered to a patient with a headache disorder including, butnot limited to, migraine, cluster headache, tension headache, secondarytypes of headache and trigeminal neuralgia.

Accordingly, in some aspects of the present invention, the methodscomprise administering an oxytocin peptide or a pharmaceuticalcomposition comprising an oxytocin peptide to an individual fortreatment of pain associated with migraine. In some aspects of thepresent invention, the methods comprise administering an oxytocinpeptide or a pharmaceutical composition comprising an oxytocin peptideto an individual for treatment of pain associated with a clusterheadache. In some aspects of the present invention, the methods compriseadministering an oxytocin peptide or a pharmaceutical compositioncomprising an oxytocin peptide to an individual for treatment of painassociated with a tension headache. In some aspects of the presentinvention, the methods comprise administering an oxytocin peptide or apharmaceutical composition comprising an oxytocin peptide to anindividual for treatment of pain associated with a secondary type ofheadache. In some aspects of the present invention, the methods compriseadministering an oxytocin peptide or a pharmaceutical compositioncomprising an oxytocin peptide to an individual for treatment of painassociated with trigeminal neuralgia. In some aspects of the presentinvention, the methods comprise prophylactic treatment formigraine-associated pain comprising administering an oxytocin peptide ora pharmaceutical composition comprising an oxytocin peptide to anindividual experiencing a migraine-associated aura prior to onset of amigraine headache. In some aspects of the present invention, the methodscomprise prophylactic treatment for cluster headache pain comprisingadministering an oxytocin peptide or a pharmaceutical compositioncomprising an oxytocin peptide to an individual after a cluster serieshas started but prior to successive headaches in the cluster series. Insome aspects of the present invention, the methods comprise prophylactictreatment for trigeminal neuralgia pain comprising administering anoxytocin peptide or a pharmaceutical composition comprising an oxytocinpeptide to an individual after trigeminal neuralgia attack but prior tosuccessive attacks.

Kits

Provided herein are kits for carrying out any of the methods describedherein. Kits are provided for use in treatment and/or prevention ofheadache and headache or head pain disorders. Kits of the inventioncomprise an oxytocin peptide in suitable packaging. Other kits of theinvention may further comprise at least one additional analgesic agent.Kits may further comprise a vasoconstrictor, at least one proteaseinhibitor and/or at least one absorption enhancer. Some kits may furthercomprise a delivery device, including but not limited to, a device forintranasal administration. Other kits may further comprise instructionsproviding information to the user and/or health care provider forcarrying out any one of the methods described herein.

Kits comprising a single component, for example an oxytocin peptide,will generally have the component enclosed in a container (e.g., a vial,ampoule, or other suitable storage container). Likewise, kits includingmore than one component may also have the reagents in containers(separately or in a mixture).

The instructions relating to the use of the kit for carrying out theinvention generally describe how the contents of the kit are used tocarry out the methods of the invention. Instructions supplied in thekits of the invention are typically written instructions on a label orpackage insert (e.g., a paper sheet included in the kit), butmachine-readable instructions (e.g., instructions carried on a magneticor optical storage disk) are also acceptable.

EXAMPLES Example 1

Activity of an analgesic agent can be tested in a rat model by studyingtreatment-induced changes in latencies (times) of withdrawal in responseto noxious heating of the skin, typically applying a stimulus to an earor a hindpaw. Thus, application of coherent or non-coherent (non-laser)radiant heat to the ear or hindpaw will elicit rapid withdrawalmovements. Latencies of withdrawal have been demonstrated to besensitive to analgesic treatments, such that analgesics increase thelatency to withdrawal. Transmucosal or transdermal administration ofanalgesic agents can be tested for regional and/or systemic analgesia.After administration of an analgesic agent an increase in latency towithdrawal time of the ear would indicate regional analgesia. A changein the latency to withdrawal time of the hindpaw would indicate whetherthere was a systemic analgesic effect, i.e. no change in the latency towithdrawal time indicates no systemic effect, while an increase inlatency to withdrawal time would indicate a systemic effect.

Rats are housed in a 12/12-hour light/dark environment and are providedfood and water ad libitum. Efforts are made to minimize discomfort andreduce the number of animals used. Rats are lightly anesthetized withurethane and placed with minimal restraint on a heating pad to maintaintheir body temperature at 37° C. A laser beam is directed via a fiberoptic cable to the rostral external part of both ears. Characteristicresponses to laser irradiation are a retraction or withdrawal of thestimulated ear for 1-3 seconds after a thermal stimulus by the laser.Laser stimulation is terminated rapidly after response of the stimulatedear or after a maximal response (cut-off) latency of 30 seconds toprevent tissue damage.

For baseline testing of latency withdrawal responses to the ear, 3pulses are applied to each ear. The stimulation site is changed aftereach pulse allowing at least 2 minutes in between 2 stimuli on the sameear. For baseline testing of latency withdrawal responses to thehindpaw, 3 pulses are applied to the hindpaw. The stimulation site ischanged after each pulse allowing at least 2 minutes in between 2stimuli on the same hindpaw. Testing sessions are videotaped foroff-line analysis of responses. The off-line analysis is performed by aninvestigator who determines the latency of withdrawal responses to thelaser stimulation and who is blinded to the treatment groups.

After measuring baseline latencies, analgesic agents are administeredintranasally. This involves 5 equal 10 μl applications to the nose bypipette for a total volume of 50 μl over 20 minutes. The effect ofdifferent doses of an agent (e.g. 10 μg oxytocin) on latency responsesis examined. To assess the local analgesic effect, the latency ofwithdrawal response to noxious heating of the ear is tested at varioustime points after agent administration. To assess the systemic analgesiceffect, the latency of withdrawal response of hindpaws to noxiousheating is tested at various time points after agent administration.

Example 2

Sprague-Dawley rats (Charles River Laboratories) were lightlyanesthetized with urethane and placed with minimal restraint on aheating pad to maintain their body temperature at 37° C. A laser beamwas directed via a fiber optic cable to the rostral external part ofboth ears or to the hindpaws as described above. Baseline withdrawallatencies were measured by delivering 4 separate stimuli with a restingperiod of approximately 15 minutes between each stimulus. 50 μl ofoxytocin in phosphate-buffered saline was intranasally administered in 5equal 10 μl applications at a dosage of 10 μg. Withdrawal latencies forboth ears and hindpaws were tested five minutes after the finalapplication of oxytocin. As described above, testing sessions werevideotaped and analyzed. Results demonstrated that intranasaladministration of oxytocin at this dosage achieved a regional analgesiceffect in the head region without a systemic analgesic effect at thehindpaw.

Rats were intranasally administered 10 μg oxytocin and withdrawallatencies were tested. Each data point represents the average, across 8animals, of latencies in response to stimulation at a particular timeafter the beginning of the test. The circles represent the withdrawallatencies after thermal stimulation to the ear in control rats treatedwith saline. The squares represent the withdrawal latencies afterthermal stimulation to the ear in rats treated with 10 μg oxytocin. Thetriangles represent the withdrawal latencies after thermal stimulationto the hindpaw in the treated rats. (FIG. 1).

Example 3

Upon presentation at the clinic, a patient is asked for a painassessment (0-10 rating on VAS). The VAS is an 11-point numerical painrating scale wherein 0 equals “no pain” and 10 equals the “worst painimaginable”. The analgesic agent is self-administered by nasalapplicator. Initially, one puff is given in each nostril. After waiting15 minutes the patient is asked again for a pain rating and any sideeffects (e.g. sedation) are assessed. If pain is still present, anotherpuff per nostril is self-administered. After another 15 minutes, painand side-effects are assessed. If pain is still present, two mote puffsof agent are self-administered. After 15 minutes, pain is rated again,and side effects are assessed. If pain is still present, a final twopuffs are given. After another 15 minutes and at 15, 30 and 60 minutesafter that, pain and side-effects are re-assessed.

Example 4

A female patient with severe headaches secondary to adult hydrocephalusand multiple shunt surgeries was seen at the clinic. The patient's painhad been unrelieved by treatment with triptans, ergotamines, andhigh-dose opiates. The patient presented with a pain rating of 8 out of10 as assessed by the procedure described herein. The patientself-administered oxytocin intranasally at a dose of 4 IU in 0.2 ml.Within 5 minutes of administering oxytocin, the patient demonstratedmild sedation, which cleared within 10 minutes. The patient's headachepain was significantly reduced by 15 minutes after administration, andwas completely gone by 30 minutes. Pain relief lasted approximately 24hours, only briefly interrupted by mild head pain that occurred withactivity. The day after treatment with oxytocin the patient reportedsome breast tenderness which resolved within 24 hours.

This patient returned to the clinic approximately 1 month later. At thisappointment the patient rated the pain as an 8 out of 10. Unbeknownst toher, the patient was first given an intranasal administration of normalsaline, in approximately the same volume as used for the oxytocinadministration (0.2 ml). No analgesic or other effect was reported bythe patient. After waiting 30 minutes, the patient was administered 4 IUof oxytocin intranasally as described above. Within 20-25 minutes, thepatient reported that the pain was completely gone. In contrast to thefirst administration there was no observed sedation, nor was there anybreast tenderness the following day. Pain returned approximately 24hours after treatment.

Example 5

A patient was seen reporting a “stress” or tension headache for whichshe rated her head pain as a 5 out of 10 as assessed by the proceduredescribed herein. The patient was treated with oxytocin administeredintranasally at a dose of 4 IU in 0.2 ml. Approximately 10-15 minutesafter administration, the patient reported that the pain was completelygone. The patient reported feeling slightly “giddy” for the first 10minutes, after which this sensation resolved. The patient reported beingpain free for approximately 48 hours.

Example 6

A patient was seen reporting a “hangover” headache which was rated as an8 out of 10 as assessed by the procedure described herein. The patientwas treated with oxytocin administered intranasally at a dose of 24 IU.The patient reported that the headache completely resolved within 15minutes.

Example 7

A patient was seen reporting having an ongoing strong headache withoccasional boring pain on the left side. The pain had lasted for morethan 2 weeks and had been diagnosed as a “cluster” headache. The patientwas treated with oxytocin administered intranasally at a dose of 16 IU.The patient reported that their headache completely resolved within 15minutes and relief lasted for 24 hours.

Example 8

A patient was seen after reporting a daily migraine which she rated as amild to moderate headache with a pain rating of 4 out of 10 as assessedby the procedure described herein. The patient was treated with oxytocinadministered intranasally at a dose of 24 IU. The patient reported thatthe oxytocin decreased the pain to a rating of 2 out of 10.

Example 9

Regional analgesia in the face region after administration of ananalgesic agent by intranasal delivery is tested in normal subjects.Study participants are selected based on inclusion/exclusion criteria,history and physical exam, laboratory tests, and other customaryprocedures. Thermal pain responses are elicited on the face, inparticular the cheek, and on an extremity, such as the hand or leg, ofhealthy normal volunteers, such that temperature thresholds for evokingpain and/or the temperature of maximal pain tolerance can be assessedand baselines established. Increasing doses of an analgesic agent areadministered to the subjects and a dose-response curve is calculated foreach stimulation site. Changes in thermal pain threshold and toleranceat the two sites can be compared so that the efficacy of an analgesicagent at a given dose in affecting facial and whole-body pain can bedetermined.

Example 10

Study of intranasal administration of oxytocin for the treatment oftrigeminal neuralgia. Ten patients suffering from trigeminal neuralgiaare enrolled in a double-blinded, randomized, cross-over study. Thetotal study duration is three weeks, sub-divided into two 1-week trialperiods set apart by a 3-day washout period. Five participants arerandomized to receive oxytocin nasal spray during the first week and toreceive placebo nasal spray during the second week. Five subjects arerandomized to the reverse order of drug treatment.

Eligibility for the study is determined by telephone interview andduring a first visit at the study center. During the first visit ofpotential participants at the study center a medical history is takenand a medical exam is performed. In particular, the diagnosis oftrigeminal neuralgia is established by one skilled in the art. Ifparticipants meet inclusion criteria and no exclusion criteria applywritten informed consent is obtained. Demographic and medical data arerecorded. Participants are randomized to treatment sequence and receiveeither oxytocin or saline placebo nasal spray. Participants receive adiary for recording outcome data. Careful instructions are given inregard to the correct application of the nasal spray and the recordingof outcome data.

Patients are instructed to apply two puffs of nasal spray in the morningof study day 1 (200 μl or 2 IU or 3.4 μg oxytocin/puff or salineplacebo; American Pharmaceutical Partners, Inc, IL). If symptomspersist, patients are instructed to increase the number of puffs by twoper treatment day (i.e., 4 puffs on study day 2, 6 puffs on study 3, upto 14 puffs on day 7).

Efficacy measures are assessed daily. Subjects are asked to record thedaily intensity and frequency of trigeminal neuralgia attacks(attack=paroxysm of pain, not individual stabs of pain). Subjects arealso asked to record the occurrence of adverse events. At the end of astudy week, subjects are asked for a global evaluation comparing howthey felt during the study week with the pre-trial condition. Patientsare also asked whether activities that trigger trigeminal neuralgiaattacks have changed when comparing the study week with the pre-trialcondition (much increased, increased, same, decreased, much decreased).

At the end of each one week trail period or at any time of aparticipant's or investigator's request, a follow-up visit at the studycenter is scheduled. During a follow-up visit all entries on the diaryare reviewed and particular questions or concerns relating to the studyare discussed.

Example 11

Study of intranasal administration of oxytocin and diclofenac for thetreatment of trigeminal neuralgia. The study is conducted as describedabove in Example 10, ten patients suffering from trigeminal neuralgiaare enrolled in a double-blinded, randomized, cross-over study. Fiveparticipants are randomized to receive diclofenac and oxytocin nasalspray during the first week and to receive diclofenac and placebo nasalspray during the second week. Five subjects are randomized to thereverse order of drug treatment.

Patients are instructed to apply two puffs of diclofenac followed fiveminutes later by two puffs of oxytocin nasal spray in the morning ofstudy day 1. Each puff contains 0.2 mg diclofenac (Novartis Ophthalmics,GA) or 2 IU or 3.4 μg oxytocin (American Pharmaceutical Partners, Inc,IL). If symptoms persist, patients are instructed to increase the numberof puffs by two per treatment day (i.e., 4 puffs on study day 2, 6 puffson study 3, up to 14 puffs on day 7).

Efficacy measures are assessed daily as described above for Example 10.

Example 12

Study of intranasal administration of oxytocin for the treatment ofmigraine. Forty patients suffering from migraine with or without auraare enrolled in a double-blinded, randomized, cross-over study. Thetotal study duration is determined by the time that elapses until apatient has experienced two migraine attacks. Twenty participants arerandomized to receive oxytocin nasal spray for treating the firstmigraine attack and to receive placebo nasal spray for treating thesecond migraine attack. Twenty subjects are randomized to the reverseorder of drug treatment.

Eligibility for the study is determined by telephone interview andduring a first visit at the study center. During the first visit ofpotential participants at the study center a medical history is takenand a medical exam is performed. In particular, the diagnosis ofmigraine headache with or without aura is established by one skilled inthe art. If participants meet inclusion criteria and no exclusioncriteria apply written informed consent is obtained. Demographic andmedical data are recorded. Participants are randomized to treatmentsequence and receive two nasal sprays containing either oxytocin orsaline placebo nasal spray. Participants receive a diary for recordingoutcome data. Careful instructions are given in regard to the correctapplication of the nasal spray and the recording of outcome data.

Once a patient identifies the onset of a migraine attack, the patient isinstructed to administer two puffs of oxytocin or saline nasal spray toeach nostril within 5 minutes. Each puff contains 2 IU or 3.4 μgoxytocin (American Pharmaceutical Partners, Inc, IL). At the time ofdrug administration a moderate headache not declining in intensityshould be present. Experiencing a mild headache or an aura only shouldnot result in self-administration of the drug. Nasal spray isadministered no later than 2 hours after the onset of the migraineheadache. If the first administration of nasal spray fails to abolish orreduce headache pain to a mild intensity within 30 minutes, the nasalspray is administered a second time. If the migraine headache is notabolished or reduced to a mild intensity within 90 minutes after thesecond administration of nasal spray, patients are allowed to takerescue medication as prescribed by one skilled in the art.

Efficacy measures are assessed daily. Subjects are asked to record theintensity of headache, absence or presence of an aura, impairment inperforming daily activities, sensitivity to light and sound and anyepisodes of nausea and vomiting. These events are recorded at thefollowing times: before and 0.5, 2, 4, and 24 hours after administeringthe nasal spray. Patients are asked to record use of rescue painmedication and the occurrence of adverse events.

After each migraine attack or at any time of the patient's orpractitioner's request, a follow-up visit at the study center isscheduled. During a follow-up visit all entries on the diary arereviewed and particular questions or concerns relating to the study arediscussed. Participants are asked to call in to the center within twodays of experiencing a migraine attack to ensure appropriate collectionof data and compliance with study protocol.

Example 13

Study of intranasal administration of oxytocin and diclofenac for thetreatment of migraine. The study is conducted as described above inExample 12, forty patients suffering from migraine with or without auraare enrolled in a double-blinded, randomized, cross-over study. Thetotal study duration is determined by the time that elapses until apatient has experienced two migraine attacks. Twenty participants arerandomized to receive oxytocin and diclofenac as nasal sprays fortreating the first migraine attack and to receive diclofenac nasal sprayonly (without oxytocin) for treating the second migraine attack. Twentysubjects are randomized to the reverse order of drug treatment.

Once a patient identifies the onset of a migraine attack, the patient isinstructed to administer two puffs of diclofenac nasal spray to eachnostril within 5 minutes. Each puff contains 0.2 mg diclofenac (NovartisOphthalmics, GA). After a five minute waiting period, two puffs ofoxytocin or placebo nasal spray are administered to each nostril. Eachpuff contains 2 IU or 3.4 μg oxytocin (American Pharmaceutical Partners,Inc, IL). At the time of drug administration a moderate headache notdeclining in intensity should be present. Experiencing a mild headacheor an aura only should not result in self-administration of drug. Nasalspray is administered no later than 2 hours after the onset of themigraine headache. If the first administration of nasal spray fails toabolish or reduce headache pain to a mild intensity within 30 minutes,the nasal spray is administered for a second time. If the migraineheadache is not abolished or reduced to a mild intensity within 90minutes after the second administration of nasal spray, patients areallowed to take rescue medication as prescribed by one skilled in theart.

Efficacy measures are assessed daily. Subjects are asked to record theintensity of headache, absence or presence of an aura, impairment inperforming daily activities, sensitivity to light and sound and anyepisodes of nausea and vomiting. These events are recorded at thefollowing times: before and 0.5, 2, 4, and 24 hours after administeringthe nasal spray. Patients are asked to record use of rescue painmedication and the occurrence of adverse events.

After each migraine attack or at any time of the patient's orpractitioner's request, a follow-up visit at the study center isscheduled. During a follow-up visit all entries on the diary arereviewed and particular questions or concerns relating to the study arediscussed. Participants are asked to call in within two days ofexperiencing a migraine attack to ensure appropriate collection of dataand compliance with study protocol.

Example 14

Sprague-Dawley rats (Charles River Laboratories) were anesthetized withisofluorane and a platinum electrode was inserted transcranially intothe trigeminal ganglion. Nerve impulses (action potential) were recordedfrom single pain sensing nerve cells in the trigeminal ganglion inresponse to application of noxious laser pulses to the face of the rats.After recording responses to several identical laser pulses, 10 nmolesof oxytocin was applied to the nose of the rats. Thereafter, identicallaser pulses were once again applied and recorded.

FIG. 2 shows the average nerve impulses per a laser pulse forpre-oxytocin and post-oxytocin treatment. Oxytocin significantly(p<0.05) reduced the neuronal response to noxious laser pulses appliedto the animal's face. These data showed that at least part of theanalgesic effect of nasal application of oxytocin was by way of directinhibition of neurons in the trigeminal nerve.

Example 15

Male Sprague-Dawley rats (Charles River Laboratories) were anesthetizedwith isoflurane and used in the following experiments. In theanesthetized rats, single unit, extracellular recordings were performedin trigeminal nucleus caudalis while stimulating the ipsilateral facialskin with constant-current bipolar electrical stimulation.Epoxylate-insulated, tungsten microelectrodes (10 MOhm) were used understereotaxic coordinate control.

FIG. 3 demonstrates the effect of intranasal oxytocin electricalstimulation-induced responses of trigeminal nucleus caudalis widedynamic range (WDR) neurons. Shown are responses (action potentials per30 stimuli) to repeated stimulation of a rat's face before oxytocinadministration (pre-oxytocin). After administration with oxytocin atapproximately 0.1 IU, responses were recorded every five minutes for 65minutes. A second administration of oxytocin at the same dosage wasadministered at approximately 70 minutes after the first dose. Theapproximate site of the administration of the electrical stimulation isindicated by the black spot on a map of the rat's face (FIG. 3B). FIG.3C shows raw data recorded during electrical stimulation before oxytocinadministration. FIG. 3D shows raw data recorded during electricalstimulation 30 minutes after intranasal oxytocin administration.

Oxytocin treatment caused a significant reduction in responses beginning10 minutes after a first administration and continued until 50 minutespost treatment when responses began to increase (FIG. 3A). Atapproximately 70 minutes after the first treatment, a second dose ofoxytocin was administered. Within 10 minutes, the second oxytocintreatment caused a significant reduction in responses. These datademonstrated that intranasal administration of oxytocin could cause alarge effect (i.e. reduction in action potentials) but also that theeffect was reproducible within a short period of time.

Although the foregoing invention has been described in some detail byway of illustration and example for purposes of clarity ofunderstanding, it will be apparent to those skilled in the art thatcertain changes and modifications may be practiced without departingfrom the invention. Therefore, the descriptions and examples should notbe construed as limiting the scope of the invention.

All publications, patents, and patent applications cited herein arehereby incorporated by reference in their entirety.

What is claimed as new and desired to be protected by Letters Patent ofthe United States is:
 1. A method for treating chronic head or facialpain associated with the trigeminal nerve comprising intranasallyadministering to an individual in need thereof an effective dose of anoxytocin peptide; wherein the chronic head or facial pain arises in atissue innervated by the trigeminal nerve or is associated with damageor trauma to the trigeminal nerve.
 2. The method according to claim 1,wherein the chronic head or facial pain is episodic.
 3. The methodaccording to claim 1, wherein the oxytocin peptide is administered tothe lower two thirds of the nasal cavity.
 4. The method according toclaim 1, wherein the oxytocin peptide is administered as apharmaceutical composition.
 5. The method according to claim 4, whereinthe pharmaceutical composition further comprises at least one additionalactive agent.
 6. The method according to claim 4, wherein thepharmaceutical composition further comprises nociceptin/orphanin FQ. 7.The method according to claim 4, wherein the pharmaceutical compositionfurther comprises an effective therapeutic amount of a vasoconstrictor.8. The method according to claim 4, wherein the pharmaceuticalcomposition further comprises at least one protease inhibitor or atleast one absorption enhancer.
 9. The method according to claim 4,wherein the pharmaceutical composition further comprises at least oneprotease inhibitor and at least one absorption enhancer.
 10. The methodaccording to claim 4, wherein the pharmaceutical composition furthercomprises one or more pharmaceutically acceptable excipients, adjuvants,diluents or stabilizers.
 11. The method according to claim 4, whereinthe pharmaceutical composition is administered as a powder, a gel, afilm, an ointment, a liquid, a suspension, a cream or a bioadhesive. 12.The method according to claim 1, wherein the effective dose is about 0.1IU to about 150 IU.
 13. The method according to claim 1, wherein theeffective dose is about 1 IU to about 100 IU.
 14. The method accordingto claim 1, wherein the effective dose is about 10 IU to about 80 IU.15. The method according to claim 1, wherein the effective dose is about4 IU to about 24 IU.
 16. A method according to claim 1, wherein theadministration results in reduction of a pain rating on the VAS of 30%or more.